I would posit that the number of morals which are absolute are so small, that it would probably constitute the objective/natural moral code. All others are perceived morals that would fall apart when faced with a true challenge to them (kill, lie, steal).
I'd refer you back to his first post on it.
I disagree. Excluding psychopaths, people have moral codes and each person's moral code is absolute. The desire for an objective, standard moral code is an expression of one's confusion and frustration as to how another's moral code could be different from one's own.
If we say, "two wrongs make a right" we are acknowledging that the wrong on our part is a moral failing that we are choosing to carry out in the face of our moral code. The need to rationalize the choice reveals that our moral code is still functioning even if we choose to not live up to it.
It is a personal code, that is basically perceived, I don't think he is arguing against that, more that your own personal code is absolute.